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 A062239 Numbers n with property that every digit is a prime factor of n. 2
 2, 3, 5, 7, 22, 33, 55, 77, 222, 333, 555, 735, 777, 2222, 2232, 2322, 2772, 3222, 3333, 3555, 5355, 5535, 5555, 5775, 7777, 22222, 22332, 22722, 23232, 23322, 23772, 27272, 32232, 32322, 33222, 33333, 33555, 35355, 35535, 37737, 53355, 53535 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS This is a regular language in base 10. Almost all members of this sequence are multiples of either 42 or 105. There are about 2/63 * 3^n members of this sequence up to 10^n. - Charles R Greathouse IV, Nov 09 2011 LINKS Harry J. Smith and Charles R Greathouse IV, Table of n, a(n) for n = 1..10000 (first 1000 terms from Smith) EXAMPLE 77322 is divisible by 7, 3 and 2. MATHEMATICA Select[Range[2, 50000], Complement[IntegerDigits[#], FactorInteger[#][[All, 1]]] == {} &] (* Alonso del Arte, Dec 05 2011 *) PROG (PARI) { n=0; for (m=1, 10^10, t=m; b=1; while (t>0, d=t%10; t=(t-d)/10; if (!isprime(d) || m%d, b=0; break)); if (b, write("b062239.txt", n++, " ", m); if (n==1000, return)) ) } \\ Harry J. Smith, Feb 17 2010 CROSSREFS Sequence in context: A062087 A162457 A084983 * A066483 A114420 A113590 Adjacent sequences:  A062236 A062237 A062238 * A062240 A062241 A062242 KEYWORD base,easy,nonn AUTHOR Erich Friedman, Jun 30 2001 STATUS approved

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Last modified October 24 07:04 EDT 2020. Contains 337975 sequences. (Running on oeis4.)